perspectives

Dietary A.

goals-a

E. Harper,2

The and

tary

goals”

Select

Human

Committee

Needs

has

on

for the United

States

The

Nutni-

proposed

(1).

fatty

acids;

4) reduce

These

cholesterol

Gussow, Johanna

con-

sumption to 300 mg/day; 5) reduce sugar consumption by 40%; 6) reduce salt consumption to 3 g/day. The goals are to be achieved by increasing the consumption of: fruits, vegetables, whole grains, poultry, fish, skim milk, and vegetable oils; and by decreasing the consumption of: whole milk,

meat, sugar, The

eggs, butterfat, salt, and fat. dietary goals

and have

according to introductory report (1) and comments

George

McGovern

at the leased stroke, diseases demic

and

been

Dr.

in

proposed to the Senator

as great

in the U.S. and 3) this

to

smoking.” The implication ments is that the dietary

proposed

as a prescription

public of goals

for

health these have

the

tion of an epidemic of killer diseases by changes in the U.S. diet and benefit to be expected is control epidemic. The

American

have

“epiwith changes that have past half century in the U.S. diet which “repre-

a threat

Journal

of

Clinical

as statebeen

prevencaused that the of the

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Nutrition,

a

signed this endorsement and Sheldon Margen and Phillip Lee contributed to the development of the goals and the report supporting them (2). They presumably accept the view that dietary modification is an

important measure for reducing the mcidence of chronic diseases that are not pnimanly

nutritional.

endorsed

The

Center

for of the

that

campaigned

ments

that

industry

in the

consumer dietary

“land

been

advoThe

Interest,

organizations

to obtain

goals,

grant

of

also

groups.

Public

advocate

actively

of the

have

of consumer

and

Science

one

ago

goals

by a number

organizations

cate

claimed

colleges

have

nutritionists

who

endorse2 years

trained

a

generally

support

the pathogenic American diet” (5). Its endorsement is presumably also given on the assumption that the dietary goals provide the basis for converting a diet that is a threat to health into one that is healthful. Those from the fruit, vegetable, cereal, fisheries, and nutritional supplement industries who endorsed the goals represent industries that would benefit if the recommendations

to reduce

tion of whole be adopted.

substantially

milk,

From

tional

the

Madison,

Wisconsin

31: FEBRUARY

1978,

were

to

appear superfiif the goals and

of

53706. Professor

pp.

eggs

of Biochemistry

University

E. V. McCollum

and

may but

Departments

Sciences,

the consump-

meat

The dietary goals cially to be innocuous

2

Nutrition

for Responsible

Ruth Eshelman, D. M. Hegsted, Dwyer, and Paul LaChance have

generation

D. M. Hegsted,

time the committee report was re(2 , 3) because 1 ) heart disease, cancer, and various other chronic are “killer diseases” that are “epiin our population,” 2) “six of the ten

demic” is associated occurred over the composition of the

310

high

statements made by

leading causes of death been linked to our diet,”

sent

foods

Council

trade association of food supplement manufacturers, drafted a resolution endorsing the dietary goals (4). Several well-known nutnitionists, Jean Mayer, Michael Latham, Joan

“die-

goals are: 1 ) increase carbohydrate intake to account for 55 to 60% of energy intake; 2) reduce fat consumption to 30% of energy intake ; 3) modify the composition of dietary fat to provide equal proportions of saturated , monounsaturated and polyunsatu-

rated

view1

Ph.D.

Senate

tion

skeptical

in nutrition

of Nutritional

310-321.

and Nutri-

Wisconsin-Madison,

Printed

Sciences.

in U.S.A.

DIETARY

the

rationale

by Federal the basis

for them agencies for food,

and education them

have

reaching trition

were

programs,

this

implications.

The would

endorsing

would

have

approach be

of diseases

tritional

that

rather

some

than

and

are

completely

not

al-

toward treat-

primarily

guidelines

nutritionally

of chronic the practice

nutritional the

adequate

diet.

adoption and treat-

diseases would be, in esof medicine with uniform

treatment

nature

of

for all, irrespective

their

health

of the

U.S.

food

supply.

of

problem

whether they were ill or well. Also, the report of the Senate Committee (1 ) represents a sweeping ment

nu-

for a whole-

Health programs that prescribed of the dietary goals for prevention ment sence,

far

in flu-

tered . Programs would be directed providing guidelines for nutritional ment

Board

to serve as health care,

as those

requested,

education

to be adopted

and were nutrition,

The

or

Select indictchanges

that would be required in the composition of most diets in order to meet the dietary goals would necessitate substantial changes in the food habits of consumers. This, in turn, would require drastic modification of the U.S. food supply. The basis for the goals, should, therefore, be extremely sound and the of substantial

U.S. public should benefits from their

The resolution “We live in the to await

the

be assured adoption.

endorsing the goals present and cannot

ultimate

trends we believe This is not a very

proof

before

states afford

correcting

to be detrimental” reassuring statement.

(4). It

is, therefore, important for nutrition scientists and educators to examine critically the basis for proposing the goals and to assess

the probability being achieved. delivered? A healthful of disease

diet

of the objectives of the goals Can what is promised be

versus

dietary

treatment

The view that general dietary recommendations for the population is an appropriate approach for dealing with chronic diseases has not been supported by the Food and Nutrition Board of the National Academy of Sciences/National Research Council (NAS/NRC) (6). The Food and Nutrition

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311

GOALS

(NAS/NRC)

has

published

Recom-

mended Dietary Allowances (RDA) since 1943, with the objective of: 1) “providing standards to serve as a goal for good nutrition”, and 2) “to encourage the development of food use practices by the population of the United States that will allow for maximum dividends in the maintenance and promotion of health” (6). The first objective has been achieved by presenting necommendations for levels of intake of specific essential nutrients judged to be adequate to meet the nutritional needs of healthy people . These recommendations are for amounts of nutrients that, if consumed by each member of a population, should be high enough to ensure that the needs of almost all will be met. The second objective has been achieved by presenting, in the various sections of the RDA bulletin, information that helps the reader to distinguish between recommendations for a healthful diet and diet therapy for diseases that are not primarily nutritional in origin. The principles underlying the approach to a healthful diet, as expressed in the RDA bulletin, are distinctly different from those of the Senate Select Committee on Nutnition and Human Needs and the onganizations and individuals who endorsed its die-

tary

goals.

The

Food

and

Nutrition

Board

emphasized that the RDA are not recommendations for chronic diseases and other conditions that require special dietary treatment and that such conditions require mdividual attention (p. 3). For individuals at risk of coronary heart disease, the RDA report acknowledges that dietary modifications appear to be indicated but reiterates that such changes must be made on an individual basis with other risk factors considened (p. 35). The report states further that there is little direct evidence to support the hypothesis that hypertension can be produced in normotensive man on the usual intakes of salt. However, the RDA report does suggest that hypertensive individuals

can benefit from Such statements tional

or

therapy

have

alleviated different

for

developed, by dietary problem

a diet make those

low

in salt

(p.

90).

it clear that nutriwho are at risk of,

a disease treatment from that

that

can

is a distinctly of providing

be

312

HARPER

guidelines for sound nutrition for the population as a whole. In fact, the Food and Nutrition Board publishes not only the RDA (6) which are recommendations for the population generally but has also published a bulletin on therapeutic nutrition (7), which provides guidelines for dietary modifications for those for whom such necommendations may be beneficial. The importance of this distinction has been emphasized by the American Medical Association in a submission to the Senate Select Committee (8). Incidence expectancy

of chronic

diseases

and life

cancer associated with smoking. Also, a rise might be anticipated from the knowledge that industrial and environmental contamination have increased steadily over the past 50 years. Life expectancy at age 65 has increased little anywhere, but since 1900 it has increased in the U.S. by two years for men and almost 5 years for women. It is obviously fallacious and misleading to call this situation an “epidemic” of “killer diseases” attributable to deterioration of the food supply or to indict the U.S. diet as “pathogenic Such statements are political, not scientific. They create unjustifiable fear of food and fear for health. .“

Diet How

valid

is the

rationale

and chronic

diseases

for the dietary

goals, i.e., the claim that the U.S. is suffering from an “epidemic” of “killer diseases” associated with changes in the national diet over the past half century? While our diet has been undergoing these assumed undesirable changes, life expectancy has increased by 20 years. It has increased since 1950, although more slowly than previously. Nutnitional deficiency diseases have all but disappeared and most infectious diseases have been effectively controlled. Infant and child mortality, in particular, have thereby been reduced far below what they were at the turn of the century. This and control of infectious diseases among all age groups has resulted in an aging population. In 1900, 4% of the U.S. population was over 65 years of age; by 1975 the proportion had increased to 10% (9). It is not surpnising, then, that the incidence of chronic diseases should increase and that heart disease and cancer should be major causes of death. Despite the aging of the population, however, U.S. health statistics (9), which were available to the Committee and all of those who endorsed -the Committee’s “dietary goals”, show that, when the incidence of heart disease and stroke are adjusted for age, the rates of occurrence of these diseases have been decreasing. The death rate from cardiovascular diseases has decreased by 30% since 1950 according to the Committee’s own report (10). The age-adjusted rate for cancer has been increasing slowly. Much of this increase is attributable to lung

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To what extent are the diseases for which the dietary goals have been prescribed nutritional diseases? Not one of them is a nutritional deficiency disease. They are all diseases of complex and not clearly understood etiology. There is great disagreement over how important nutrition is as a factor in their development. This is accepted by even the most ardent proponents of dietary treatment and was acknowledged by Dr.

Hegsted dietary

in his goals

comments

report

was

at the released

time (1

,

the

3).

Cancer Evidence of a relationship between diet and cancer is meager and tenuous at best (11-13). Much of the evidence for a relationship between diet composition and cancer is based on differences in the geographical distribution of different types of cancer.

Even

then

the

relationship

with cancer generally, types of the disease. of one type of cancer

or population

group

is not

so much

but with individual Thus, a low incidence in a particular region

may

be associated

with

a high incidence of another type (1 1 ) . Irradiation, to which we are all exposed naturally, will produce cancer. Various industrial and environmental contaminants, some of them produced by microorganisms that grow on plant products, are known to produce cancer. Undoubtedly some of these are contaminants in the food supply but there is no direct evidence that either a shift toward a higher proportion of foods of plant origin in the diet or modification of

DIETARY

the this

composition problem.

of

Cardiovascular

A major

the

diet

will

decrease

disease

thrust

of the

report

on dietary

goals (1 ) is that modification of the supply will control heart disease ; yet, 30 years of study of the relationship

tween

diet

and

heart

disease

has

food over be-

produced

more controversy than definitive results (14). In epidemiological studies, a high incidence of heart disease is found in association with a high intake of calories, a high intake of animal protein, a high intake of saturated fat, a high intake of cholesterol, a high intake of sugar and with various other indicators of a high standard of living (15, pp. 382-386). According to Dr. Levy in a statement before the Select Committee , despite these associations and extensive investigation of diet and heart disease in both

man

and

animals,

tary modification erosclerosis “is fact” (16).

Heart

disease

the

assumption

will prevent still a hypothesis

is associated

that

die-

or delay athand not a

with

genetic

predisposition, obesity, sex, inactivity, smoking, hypertension, diabetes, stress and diet and undoubtedly other factors as well (15 , p. 293). In the report on dietary goals,

Drs. McGill and Mott are quoted as saying “There is strong evidence suggesting that, for those overweight, the best protection against heart disease is weight reduction,” and from Drs. Ashley and Kannel “it is uncertain whether the nutrient composition of excess calories, derived largely from saturated (fat) calories accompanied by cholesterol and simple carbohydrates, or the positive energy balance per Se, 5 important.” Those who prepared the report concluded, nevertheless, that the U.S. intake of sugar, saturated fat and cholesterol are major risk factors. This conclusion required that all contrary views be ignored. It represents unwillingness to recognize that differences of opinion among scientists and health professionals concerning the role of diet in the etiology of heart disease are great, mainly because knowledge of the subject is inadequate. When those who work actively with this problem disagree so completely, there can be no sound basis for recommend-

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313

GOALS

ing the

radical changes in the composition of U.S. diet. Also, it is incumbent upon those who are recommending a high intake of polyunsaturated fats in order to reduce the risk of heart disease to provide evidence that this is not deleterious. It is difficult to envision

that

mammals

unsaturated

consumed fatty

a diet before

high

in poly-

advent of food processing on a large scale . Knowledge of the safety of high intakes of polyunsaturated fatty acids over a long period of time is limited. In the dietary goals report (p. 33), Dr. Wynder is quoted as saying that “incidence of cancer seems to be related as much to (intake of) unsaturated as saturated fats.”

A relationship

acids

between

the

elevated

serum

cholesterol and certain types of hyperlipoproteinamias and susceptibility to heart disease is reasonably well established (16). So is the fact that many who are genetically susceptible to elevated blood lipids and cholesterol respond to dietary treatment (17). Such treatment is nutritional therapy for a chronic disease, just as is dietary treatment of mild diabetes. The logical and scientific approach to either curative or preventive medicine is to identify those who are at risk and provide them with an appropriate set of dietary guidelines and an opportunity for health care, as is recommended by the Food and Nutrition Board in the RDA bulletin (6) and by authors of authoritative textbooks on human and clinical nutrition (18). In a recent critique of the dietary goals (19), Dr. Phillip White has emphasized that there is no basis for uniform treatment of different forms of various chronic diseases. Accurate knowledge of both the problem and the patient is required in order to provide appropriate treatment, and therapy must often be highly individualized. The ultimate road to control of cardiovascular disease is through an effective research program. More knowledge is needed, for

example,

of

how

cholesterol

synthesis

regulated in the body and of factors, including genetic and dietary ones, that interfere with this regulation. Identification of factors that block the regulation of this system, particularly if such factors may be present in some foods, would provide the potential for delaying the onset of heart disease.

is

314

HARPER

However, even when the etiology of heart disease is understood, it is doubtful that any general recommendation for the population will be justified. Current knowledge of hereditary differences among people is already sufficient to indicate this.

might from many from

deter many of those with this ailment receiving appropriate treatment and of those whose need for salt is high, consuming enough.

Diet

and health

Hypertension

With life expectancy having increased by 20 years since 1900; with the age-related incidence of heart disease decreasing since 1950 and that of stroke since 1930; with the average amount of time lost from work, in the U.S., including work loss from accidents, being only between 5 and 6 days per year (9); and with nutrition survey reports indicating that at least 85 % of people sunveyed show no evidence of nutritional deficits and that the major deficit is mild iron deficiency (21 , 22); there can be no doubt but that the food supply is sound if it is used appropriately, as it obviously is by most people. The fact that the major health problems of the U.S. are chronic diseases associated with aging is, in itself, evidence of this. The countries with health statistics equivalent to or better than ours in 1975 were those of western Europe and northern North America where diets resemble those of the U.S. When our knowledge of diet and health is viewed in proper perspective, a far stronger case can be made for concluding that the changes in our food supply

and

salt

intake

Hypertension is a common disease in the U.S. The dietary goals report (p. 49) (1) quotes Drs. Meneely and Battarbee to the effect that “excessive salt intake (is) noxious per se” but the report fails to quote from the same article (20) that the desirable upper limit of salt intake is controversial and that a low sodium intake lowers high blood pressure in some but not others and that a high sodium intake increases blood pressure in some but not in others. Hypertension, they state, is only partially understood. For many people it is important to control salt intake. For those with congestive heart failure control of salt intake is essential. Dietary recommendations for such patients range from 2 to 5 g of salt per day ( 1 8) . The dietary goals report extrapolates, without justification, from information about the estimated human requirements for sodium to therapeutic treatment of hypertension for the entire population. This is comparable to recommending that protein intake of the U.S. population should be only 35 g/day because that is the average requirement and is recommended for patients with renal failure.

A salt intake

of 3 g per person

per

day

is

unrealistic and unattainable for the general population and unnecessary for most people. It overlooks completely the high need for salt of athletes and those working in a hot environment. A meaningful recommendation would be to propose that a concerted effort be made to identify those with hypertension and those who may be prone toward developing hypertension and provide them with an effective program of health education. The only way of controlling hypertension in most persons is through treatment with some highly effective drugs and by using reduced salt intake as an adjunct to drug therapy, not as a substitute for it. In fact, a Federal recommendation for low salt intake as a means of avoiding hypertension

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during

this

century

with improved niorating health. Nevertheless, cally a healthy

complacency problems. relationships

health

in this century

have

health evidence people

about

than

are

associated with

that we are is no reason

health

However, between

problems

been

rather

and

detebasifor

nutrition

we must recognize that diet and most current

complex

and

poorly

understood. These problems will not be solved by drawing unwarranted conclusions from insufficient and inappropriate research results, nor will they be solved by accepting simplistic proposals as if they were panaceas. They will be solved only by careful, imaginative, well-designed research that provides valid answers to difficult questions, particularly to the question of what role nutrition has in aging and in the development of chronic diseases. This was emphasized by Dr. E. L. Wynder in testimony

DIETARY

before the Select Committee (23). Nutnitional diseases and infectious diseases were controlled only after painstaking research had provided accurate basic knowledge about their causes and how to treat them.

The

same

will

Current

be true

nutrition

How

does the

major

U.S.

and

the

diseases.

problems

the

with

of chronic

dietary

goals

nutrition

topics

report

problems

that

are

deal of

the

of concern

to

the public? Is the dietary goals report a carefully developed, sound scientific document that treats these subjects in an objective way that deserves the attention of nutnitionists and of the public generally? Dental

caries

Dental public bulletin

caries

is recognized

health problem of the Food

(6) emphasizes

that

foods

forms of simple carbohydrates bohydrates that are not

oral ies

cavity and

tooth

that

decay

promptly”)

a major

containing

such

36).

sticky

(“simple cleared from

promote

avoiding

(p.

as

in the U.S. The RDA and Nutrition Board

dental

foods

can

It states

addition of fluoride to bring tion in the water supply to

carthe

carreduce

further

that

the concentra1 mg/liter “has

proved to be a safe, economical cient way to reduce the incidence

and effiof tooth

decay”

Nutrition

Board water

(p.

98).

The

“recommends supplies

where

tion

is attributed

without

any

and

of public

it is needed

of low natural fluoride In the report on decay

Food

fluoridation levels” dietary to

high

because

(p. 99). goals, dental sugar

acknowledgement

consump-

of the

importance of the form in which sugar is consumed nor of the fact that all simple carbohydrates in sticky form, whether they are in highly refined products or dried fruits

(which can of sucrose),

contain as much as 50 to 60% will promote dental caries. The

one public health procedure that has proven effective in reducing the incidence of dental caries, fluoridation of the water supply, is not mentioned in the report. This is a serious oversight in any set of recommendations for improvement of the dental health of consumers. Dr. Hegsted stated that the dietary goals

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315

GOALS

“cannot be based on scientific evidence alone but must represent some compromise with reality” (3). A recommendation for controlling dental caries through reducing sugar consumption is not a compromise with reality; it is a disordening of priorities. The American Dental Association and many nutnitionists have been recommending this for decades. It is a recommendation that has proven to be futile and essentially gratuitous. The value of fluoridation of drinking water for the control of dental caries has been demonstrated through extensive research. More to the point than a proposal for reducing sugar intake would be a necommendation for a program of further research on the control of dental caries in a population that, even if it were to reduce its sugar intake by half, would still have enough sticky carbohydrates to contribute to the widespread occurrence of dental caries. Considerable progress has been made in research on the control of dental caries through immunization (24). Dental caries is an infectious disease and success in this century in controlling infectious diseases has been through immunization. Obesity Obesity is recognized as another important public health problem in our society. It is mentioned in the report on dietary goals (1) primarily in relation to the high risk of chronic diseases among the obese (p. 32). The authors of the report suggest (p. 20) that adoption of the “dietary goals” may reduce obesity because the “high water content and bulk of fruits and vegetables and the bulk of whole grains can bring satisfaction of appetite more quickly than do foods high in fat and sugar.” Physiologists established early in this century that fat is desired because it has the greatest satiating value of any food constituent. They also established

that

organisms

adjust

rapidly

when

they

are

fed high calorie diets that have been diluted with water, carbohydrate or fiber and maintain their energy (calorie) intakes at what they were before the diet was diluted (25). Although it is easier to overeat fat than any other energy source it is not difficult to overeat starch if the supply is abundant.

316

HARPER

Nutritionists and physicians have learned through long experience that changing the composition of the diet does not increase the 5 to 10% success rate achieved in the treatment of obesity (26). In fact, dietary treatment of obesity has been so unsuccessful that surgeons have been taking over treatment of the more severe cases with an operation for by-passing a major part of the small intestine an operation that creates new health and nutrition problems. The Food and Nutrition Board in the -

RDA

bulletin

(6)

recognizes

that

“contin-

ued excessive intake of energy leads to obesity and is detrimental to health” (pp. 8, 13). It recommends that those “who gain excessive amounts of body fat while habitually consuming (the amount of calories) appropriate for their body weight, sex and age should increase their physical activity until the desired weight balance is achieved. Energy intake should be reduced below the

(RDA)

as but

one

of several

sound program of weight cludes increased exercise.” for this recommendation

RDA

bulletin,

among

them

measures control Several are cited

in a that inreasons in the

the observation

of Dr. Jean Mayer who endorsed the dietary goals, that food intake is not usually wellregulated when energy expenditure is low. The report on dietary goals (1 ) does not mention the importance of exercise and physical work in programs for control of obesity nor does it acknowledge the need for individual treatment or unique group therapy for this chronic condition yet Dr. Bray in his statement before the Senate Select Committee emphasized the importance of all of these (26). Current knowledge does not support a recommendation for control of obesity through modification of the composition of the diet (26). The crucial problem in dealing with obesity is to learn why people overeat, a question to which we have only fragmentary answers. It is necessary to learn, through basic research, how food intake is controlled, to what extent differences in efficiency of energy utilization can account for problems in body weight regulation and about motivation that starts and stops eating. Only when we have this fundamental knowledge will those who practice nutrition

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be able to do more than and suggest willpower obesity.

offer for

calorie guides prevention of

Anemia The

RDA

bulletin

of the Food

and

Nutni-

tion Board (6) notes “the high incidence of iron deficiency in the population surveyed in the National Nutrition Surt’ey.” The “dietary goals” of the Senate Select Committee (1) do not include a recommendation for the major nutritional deficiency problem that has been identified in all U.S. nutrition surveys. In fact, the dietary goals recommend reduction in the consumption of meat, one of the best sources of iron and other essential trace minerals in the U.S. food supply. In the RDA bulletin it is noted that women of child-bearing age have difficulty in meeting their needs for iron from typical

American not

diets,

contain

Iron

large

as it occurs

especially

if their

diets

amounts

of meat

(p.

in meats

is a reliable

of available iron; meat protein shown to increase the absorption forms of iron (p. 93). Although incidence of anemia encountered

U.S.

may

be attributable

do 94).

source has been of other the high in the

in part

to infec-

tious and chronic diseases rather than simply to iron deficiency, it is difficult to accept a set of dietary goals that: 1 ) fails to recognize the one public health problem that is generally acknowledged to be due to nutritional inadequacy, and 2) includes recommendations that would decrease the consumption of the nutrient that is already in shortest supply in the U.S. diet. Sugar content

A

and

other

substantial

foods

part

with

of

low

the

nutrient

dietary

goals

report (1 ) deals with the importance of reducing sugar consumption under the heading “Nutrient Danger” (p. 44). Use of this heading indicates that conclusions about the effects of sugar were drawn before the evidence was assessed. A committee ap-

pointed by the Federation cieties for Experimental at least 145 publications held a public hearing committee concluded

of American SoBiology reviewed on sucrose and on the subject. The after this extensive

DIETARY

review (27): “Other than the contribution made to (the development of) dental caries there is no clear evidence in the available information on sucrose that demonstrates a hazard to the public when used at levels that are now current and in the manner now practiced .“

A sweet

taste

is innate,

not

only

to man

but to many other animals as well. On the whole , a sweet or neutral taste is a reasonable guide to safe foods and may well have developed as a characteristic with survival value . Sweet foods have hedonistic value and since we eat many foods for pleasure rather than for nutrients it is a moral rather than a biological judgment to suggest that we should forego the enjoyment of highly desired foods for uncertain and unproven benefits. The Dutch and the Swedes, who exceed us in life expectancy, consume as much or more sugar than we do . In fact, the countries with the highest life expectancies are those in which sugar consumption is high. Alcohol, an energy source over-consumption of which can represent a hazard receives little attention in the dietary goals report. A cocktail and two glasses of wine or two bottles of beer can provide from 10 to 15% of daily energy intake for an adult.

Salad

oils,

and

provide a high ergy requirement cant quantities

The

various

refined

proportion without of most

bias of the report

fats

can

also

of the daily enproviding signifiessential nutrients.

is clearly

evident

from

these omissions and the way sugar consumption is dealt with. Emphasis is placed in the report on increased soft drink consumption resulting in milk being displaced from its

position

as the second

most

frequently

con-

sumed beverage . Yet a table in the report (p. 46) shows: 1 ) that milk consumption has declined little (the small decline that has occurred is probably the result of the lower milk intake of an aging population); 2) the increase in soft drink consumption has been accompanied by a substantial decrease in coffee consumption. Much is also made of the large amount of sugar in processed foods and how this has contributed to high sugar consumption. As sugar consumption has remained unchanged since 1925, the amount of sugar now consumed in soft

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GOALS

317

drinks and processed foods (70 pounds now versus 28 pounds pen capita in 1925) was consumed previously in coffee and foods prepared and eaten in the home (65 pounds in 1925 versus 25 pounds now) (1, p. 44). The report itself emphasizes that the major change in the composition of the U.S. diet during this century has been substitution of fat for starch. The Senate Select Committee report (1) points out that a high intake of sugar “increases the potential for depriving the body of essential micronutnients” (p. 44). This subject is also dealt with in the RDA report (6), but with much different emphasis: “Many Americans derive a large part (30% or more) of their energy from relatively pure sugars, fats and alcohol, which provide almost no vitamins and minerals, or at best only a narrow spectrum of nutrients. These food consumption trends can have important adverse consequences on the overall qualtity of the diet” (p. 33). This is not simply a problem of sugar intake . Reduction of sugar intake by itself, provides no assunance of better health for most people but limiting the intake of all foods with low nutrient content, including fats and alcohol, is an important nutrition guideline for avoiding inadequate intakes of essential nutrients. We know that people can tolerate considenable dilution of their diets with alcohol, sugar and refined fat if the other foods consumed are rich in essential nutrients but we are not sure of the limits of dilution. It probably lies somewhere between 20 and 30% of total caloric intake for those with a highly varied diet and moderate energy expenditure but considerably less than that if total energy intake is low for any reason. The Food and Nutrition Board (6) emphasizes that for the aging, and during illness or rehabilitation from illness, if appetite is curtailed, it is important to ensure that the smaller quantities of food consumed are well-selected to provide the needed amounts of essential nutrients (pp. 1 1-i 2). This would apply also to those who are restricting food intake as part of a weight-reducing regimen. The solution for this problem is through appropriate nutrition education, not through altering the U.S. food supply.

318

HARPER

Animal

versus

plant

foods

The recommendation to increase consumption of cereal grains and other plant products and decrease consumption of animal products, especially meat and eggs, would result in a reduction in the quality of protein in the U.S. diet. If as much as 60% of calories were to be obtained from canbohydrate and 30% from fat, the upper end of the proposed range of dietary goals, not only would protein quality be reduced but for many people quantity would be reduced as well. In the dietary goals report (1), the value of plant products as sources of nutnients is emphasized by comparing the nutnient content of fruits with that of purified fats and carbohydrates (p. 19) rather than with that of meat, milk, and eggs. The RDA bulletin (6) cautions “Protein intakes that exceed the RDA are often desirable since low protein diets usually contain only small amounts of animal products and thus tend to be unpalatable and low in important trace nutrients” (pp. 13, 38). The overall recommendation to replace animal products with plant products makes it seem as if the proponents of dietary goals are advocating a return to the diet of the past century and toward that of the less technologically developed parts of the world where nutrition problems are of major concern. If such a recommendation were to be adopted as part of a set of Federal dietary goals and these were to be widely publicized, it is important to consider the possible ramifications. For adults the problem of meeting nutritional needs would not be cnitical, but if families adopted such a goal and

went

to extremes,

there

would

be the poten-

tial for a shift in the diets of young children toward cereal grains and plant products that are bulky, low in energy and often low in their content of essential nutrients. It would be a long step backward if a set of dietary goals based on providing adults with therapy for chronic diseases that require individual attention, were to be recommended generally and result in deterioration of the diets of young children.

Oversights It goals

in the dietary

is difficult, document

goals

after reading the dietary critically, to avoid the con-

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elusion that the dietary goals were preconceived and then evidence was marshalled to support them . I ) Anemia attributable to iron deficiency, which is considered to be the major nutritional problem of the U.S., is not mentioned and a recommendation is made for reducing the consumption of meat, a major source of iron in the food supply. 2) Major emphasis for the control of dental caries is placed exclusively on lowering sugar consumption rather than on a measure that has proven effective, fluoridation of the water supply. 3) The recommendation for reducing salt consumption is a recommendation for treating the entire nation for hypertension even though many may have a high need for salt. Also, meats, with 45 mg of sodium per 100 kcal, are listed as high salt foods whereas whole wheat bread with 216 mg of sodium per 100 kcal is listed as only moderately high (p. 50). 4) The nutrient content of plant products is not compared with that of animal products but with that of purified sugars and fats. 5) Processed foods are denigrated for their contribution to the sugar content of the diet, yet sugar consumption has remained constant for 50 years. 6) The report states that views on the role of diet in the development of heart disease and other chronic diseases are controversial but does not hesitate to conclude that the proposed dietary changes will be beneficial. 7) Obesity is cited as an important nutritional problem but the only recommendation for controlling it-to alter the composition of the diet is a discredited one. -

The dietary goals report cally sound: it is a political

is not

scientifi-

and moralistic document. It will appeal to those who accept pseudoscientific reasoning about the wisdom of returning to the diet of last century and to that of the peasant of poor countries. Back to nature movements have occurred regularly throughout history when the problems to be solved were complex and solutions for them were not readily attainable. Treatment with some natural product assumed to have magical properties has often been the substitute for appropriate knowledge. We had the medieval doctrine of signatures. The thistle with prickly leaves was appropriate as a treatment for internal prickling. Port wine, which was red, was

DIETARY

appropriate

An

treatment

occasionally

one

for

pale

of these

blood

chance

(28).

reme-

dies proved effective, for example, digitalis for heart disease. But why, when we have the ability to apply the scientific method to solve our problems, should we fall back on preconceived conclusions because the answers we would like to have cannot be obtained as quickly as we want them through sound, basic research? It would have been reassuring if the Senate Select Committee and its advisors had been modest enough to admit: “We do not know enough to propose a specific dietary regimen for the control of obesity and should not pretend that we do if we want to maintain credibility. However, we do know that innovative methods are required in orden to aid people to decrease their consumption of food and that increased physical activity is helpful for many.” “We know that consumption of sticky sugary foods, particularly between meals, increases the probability of dental caries but we doubt that a recommendation for reduction of sugar consumption is realistic. However, we can necommend oral hygiene and fluoridation of the water supply to help control this infectious disease.” “We know that nutritional problems occur primarily when dietary choice is restricted and only rarely when diets provide a wide variety of foods. We are concerned about young children and women of child bearing age obtaining enough iron in their diets and recognize that meat is an important source of this nutrient

for

them.”

“We

can

formulate

diets,

and

even nutrient solutions for parenteral feeding, that are satisfactory, nutritionally adequate and effective in preventing nutritional diseases. However, we do not have knowledge that would permit us to make general recommendations for modification of the diet of the population as a whole as a means of controlling chronic diseases.” “We can make some meaningful dietary recommendations for those who have, or are at risk of developing, certain chronic diseases if we study each individual carefully. However, we would hesitate to make general recommendations for drastic alteration of the U.S. diet because we do not know what the longrange consequences of adoption of such recommendations might be.” “We know

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GOALS

319

that the nutritional quality of a diet is reduced if foods high in nutrient content are displaced by foods low in nutrient content. We do not know how much different diets can be diluted with highly purified products before the reduction in nutritional quality becomes of concern. We know that this is not simply a problem of sugar consumption, therefore, we would caution against the use of excessive amounts of cooking oils, alcohol, highly refined sugars and starches, and other foods with low nutrient content.”

On panaceas

and common

sense

The rationale for the proposed dietary goals for the treatment of chronic diseases bears a striking resemblance to that of the nutrition healers who recommend large doses of vitamins to prevent colds, influenza and cancer and large doses of vitamin E to ensure sexual potency and freedom from heart disease and aging. The nutritional healers and the proponents of the dietary goals both say there are no risks involved and important benefits can be expected. This is also the stock in trade of food faddists and nutritional supplement companies. Neither consumers nor nutrition professionals stand to gain from this approach to health problems. It has great potential for undermining both the science of nutrition and nutrition education. It raises false hopes among consumers on inadequate grounds. It is a promise to deliver a panacea that cannot be delivered. The necromancers of old promised to provide the elixir of life but their credibility was eventually undermined by the rise of science The international experts who proposed protein supplements and amino acids fortification for the prevention and cure of world-wide malnutrition lost credibility when that simplistic solution for a complex problem was proven invalid. There is no need for nutritionists to fall into this trap again by joining those who would promote a simplistic nutritional cure for all the ailments of old age. In fact, it would not be important to discuss the dietary goals at all were it not for the possibility that they might be adopted and thereby influence Federal nutrition policy to the detriment of both the consumer and the professional nutritionist. .

320

HARPER

Ruth Gay stated in a recent article (28) “Although we learned long ago to abandon magical thinking in connection with weather, crops, the care of animals and other natural phenomena, it still has us in its grip when we think of our diet. Our latest thinking about food, based on fear, is proportionately retrograde-willing to accept, indeed seeking out, the consolations of magic, the mute practices of peasants, and the quaint devices of folklore.”

The

amount

of misinformation

about

nu-

tnition that is circulated widely, especially by those who profit from doing so, is overwhelming. This is responsible, in large measure, for the attitudes so accurately and so succinctly described by Ruth Gay. There is evidence that people are less confident about their knowledge of nutrition today than they were a few years ago (29), undoubtedly because of the difficulty they have in distinguishing between the sense and the nonsense written about the subject.

The

worst

of the

misinformation,

and

the

most widely read and quoted, does not come mainly from magazine and television advertising of food products, as the Senate Select Committee concludes (1). It comes from food supplement promoters, from authors who earn a living by selling sensational nutrition misinformation and from a wide variety of pseudonutrition experts (30, 31).

The

Senate

addressed gated the

A

Select

Committee

might

itself to this problem and sources of misinformation

Federally-supported

nutrition

McGovern the United 1977.

3.

HEGSTED,

4

States. Council

.

5.

References 1. Select Committee on Nutrition and Human Needs, U.S. Senate. Dietary Goals for the United States. U.S. Government Printing Office, 1977. 2. MCGOVERN, G. Statement of Senator George

Downloaded from https://academic.oup.com/ajcn/article-abstract/31/2/310/4650466 by University of Leeds user on 07 May 2018

M.

Dietary

goals

dietary

goals

.

.

D.C.,

11. 12.

13.

en-

pre-

18, 1976.

1952.

14. 15.

1975.

Select Committee

Human

Diet related Washington,

part

on Nutrition and to killer diseases II, D.C.: U.S. Government

neoplastic development. American Cancer Society, Goiu, G. B. Statement Related to Killer Diseases, 1 976 before the Select and Human Needs, p.

Printing

Of-

Government WERX#{212}, L. Risk

ease-facts STAMLER, Diseases

In:

Nutrition and Cancer, 1972. July 28, 1976. In: Diet Hearings July 27, 28, Committee on Nutrition

166. Washington, D.C.: Printing Office, 1976. factors and coronary heart disHeart

J. 91:

J. Statement in Diet II, part 1 . Hearings

or fancy?

Related

on

Nutrition

Am

and

Committee ruary

on Nutrition

1 , 2, 1977.

and

Washington,

before

Human

1 , 2, 1977. Washington, emment Printing Office, 1977. 16. LEVY, R. I. Statement in Diet Diseases II, part 1 . Hearings ruary

18 .

Needs.

1 , p. 82.

fice,1977. ROSE, D. P. Update: diet, nutrition, and cancer. Prof. Nutr. 8: No. 4, 1, 1976. SHn.s, M. E. Nutritional and dietary factors in

Committee

17 .

submitHuman

Needs, U.S. Senate. Re: Dietary goals for the United States, April 18, 1977. National Center for Health Statistics, Health in the United States. A chartbook. Rockville, Maryland: U.S. Department of Health, Education and

U.S.

20.

April

American Medical Association . Statement ted to Select Committee on Nutrition and

Welfare,

10.

19.

United

sented to members of the Senate Select Committee on Nutrition and Human Needs. May 12, 1977. Comm. Nutr. Inst. Weekly Report 7, No. 21 , p. 4, 1977. Center for Science in the Public Interest . The

234,

9

the

Recommended dietary allowances . Washington , D .C . : National Academy of Sciences/National Research Council, 1974. Food and Nutrition Board. Therapeutic nutrition. Washington, D.C.: National Academy of Sciences/National Research Council, Publication No.

7.

8

for

. Resolution the United States

for

terrible ten. Washington, 6. Food and Nutrition Board.

educa-

tion program based on established knowledge that would help to teach people what sound nutrition practices are and more particularly what can, and what cannot, be expected from following such practices, would be of infinitely more value to the general public than a set of recommendations for nutritional treatment of chronic diseases based on fear of food and fear for health and proposed on the basis of highly selected information under the guise of dietary goals.

D.

Nutr. Notes 13: 4, 1977. for Responsible Nutrition

dorsing

have investifully.

on the publication of dietary goals of States. Press release, January 14,

87, the

Select

Needs.

Feb-

U.S.

Gov-

D.C.: Related

to Killer

before the Human Needs.

D.C.,

1976.

to Killer

U.S.

Select Feb-

Gov-

ernment Printing Office, 1977, pp. 29-33. National Heart and Lung Institute . The dietary management of hyperlipoproteinemia. DHEW Publication No. (NIH) 76-110, reprinted 1974. GooDHART, R. S . , AND M . E . SHIis . Modern

Nutrition in Health and Disease. Philadelphia: Lea and Febiger, 1973. WHrra, P. L. The realism of dietary goals. Nutr. Notes 13: No. 2, 4-5, 1977. MENEELY, G. K., AND H. D. BATrARBEE. Sodium and potassium. Chapter 26 In: Present Knowledge in Nutrition, 4th Ed. Washington, D.C.: The Nutrition Foundation, 1976.

DIETARY

21

.

Ten-State chemical.

Nutrition Department Publication

Welfare

23.

Bio-

on

U.S.

Nutrition

T. Silverstone. Berlin: 1976, pp. 177-206.

No.

26.

Department

and

Human

Needs,

July

27,

27.

28.

25.

Downloaded from https://academic.oup.com/ajcn/article-abstract/31/2/310/4650466 by University of Leeds user on 07 May 2018

G.

Statement

in

Diet

Related

to

Killer

Life Sciences Research Office. Evaluation of the Health Aspects of Sucrose as a Food Ingredient.

Bethesda,

Maryland:

cieties

Experimental

GAY,

for

Rum.

Federation Biology,

Fear of food.

Am.

of American 1976. Scholar

45:

So437,

1976. 29.

ing Office,

24.

BRAY,

Konferenzen,

Diseases II, part 2. Hearings before Select Committee on Nutrition and Human Needs, February 1, 2, 1977. Washington, D.C., U.S. Government Printing Office, 1977, pp. 96-107.

28,

1976. Washington, D.C., U.S. Government Print1976, pp. 197-201. MESTECKY, J. Introduction to the structural and cellular aspects of the secretory IgA system. J. Dental Res. 55: C98-C101, 1976. HARPER, A. E., AND P. C. BOYLE. Nutrients and food intake. In: Appetite and Food Intake, edited

Dahlem

by

and

(HSM) 72-8132. Atof Health, Education, and Welfare, Center for Disease Control, 1972. Preliminary findings of the First Health and Nutrilion Examination Survey, U.S. 1971-1972. Dietary Intake and Biochemical Findings. DHEW Publication No. (HRA) 74-1219-1. Washington, D.C.: U.S. Government Printing Office, 1974. WYNDER, E. L. Statement in Diet Related to Killer Diseases. Hearings before Select Committee lanta:

22.

Survey, 1968-1970. IV. of Health, Education

321

GOALS

30. 31.

Mills. A Summary Report on U.S. Consumer Knowledge, Attitudes and Practice About Nutrition. Minneapolis: General Mills, Inc., 1977. WHrrE, P. L. Nutrition misinformation and food faddism. Nutr. Rev. 32: Suppl. No. 1, 1974. BAUETr, S., AND G. KNIGHT. The Health Robbers. Philadelphia: G. F. Stickley Co., 1976. General